Ammunition



Patented Apr. 7, 1942 5 ATEN was Bran, museum,

'ington Delaware m, assignor to Rem- Company, Inc., a corporation of No Drawing. Application July 5, 1940,

Serial No. 344,114

3 Cla.

Thi invention relates to ammunition, and particularly to priming compositions for use in ammunition. In priming compositions such as usually employed in small arms ammunition, it

is customaryto use ground glass to assist in sensitizing the composition. A priming composition usually comprises a combustion initiator, a fuel, an oxidizer, and. if necessary, a frictionator such as ground glass. The frictionator orground glass is particularly necessary in the usual rimflre cartridge, although it may'also be useful in a centerflre priming mixture. Ground glass apparently has the required sharp edges and hardness to produce the necessary friction'or sensitization as the primer is struck a blow by the firing pin to cause the mixture to be properly ignited.

There have been many attempts to substitute other materials for groundglass, but none of these have been entirely satisfactory for various reasons. One of the principal reasons appears to be that the broken pieces do not have the requisite sharpedges or hardness to properly function as indicated. Most minerals upon being comminuted to a suitable granulation tend to break into particles having no jagged edges or sharp corners. The irictionator or substances used must be stable so as to not reduce the stability of the priming composition, and particularly under high humidity at elevated temperatures. It has been found by the present invention that a comminuted natural occurring glass can be substituted for ground glass and that the natural occurring-glass will satisfactorily meet the requirements of a frictionator.

Other objects of the invention will become apparent to those skilled in the art when the following description is read.

It has been found that a natural occurring glass will perform satisfactorily which has the chemical composition 0!:

Per cent 'Silica 59.50 Ferric oxide 0.35 Alumina 25.00 Calcium oxide 6.90 Soda and. potash 7.80 Loss on ignition 0.45

i The mineralogical composition of this natural occurring glass is: 23% zoisite (HCa Al Si O r- Si1ica 29.7%,

alumina 33.7%, lime 24.6%,

water 2%, belongs to epidote family of silicate minerals Hardness 66.5%.)

55% albite- Q- (NaAlSi O =Silica 68.7%, alumina 19.5%, soda 1l.8%- is one of the plagioclase feldspars-Hardness 6.)

titanite (CaTiSiO =Silica 30.6%, titanium oxide 40.8%, lime 28.6%Hardness 55.5%.)-

2% apatite (CadCaF) Pos -Hardness 5.

clino-roisite- (A monoclinic or triclinic modification of zoisite.)

2% quartz (S170)z=Sl11C8. 100%Hardness 13% sericite- (HzKA1 (SlO -iS. a mica- Hardness 22.5%.)

5% microcline (KA1Si O =si1ica 64.8%, alumine. 18.4%, potash 16.9 is a fe1dspar-Hardncss 6 6.5%.)

It is seen that the natural occurring glass which may be used consists principally of silicates, feldspar-s and mice. with small percentages of other ingredients such as apatite and quartz. The hardness of the natural occurring glass that was used is between 6 and 7 on the Moh scale, which is similar to that of glass. It is evident that the minerals are present in a microcrystalline condition and that no crystals will be visible to the naked eye.

The natural occurring glass referred to can Per cent Tetrazene 2 Lead styphnate 40 Lead nitrate 30 Lead sulphocyanate 8 Natural occurring glass 20 This priming composition was subjected to the usual humidity tests and it was iound that it satisfactorily withstands the same.

Otherexamples of priming mixtures in which natural occurring glass will work are:

Per cent Lead styphna 33 Lead hypophosphite 10 Lead nitrate 12 Barium nitra 20 Lead peroxide Natural occurring glass 20 Lead styphnate 20 Mercury ifulminate 20 Barium nitra 30 Calcium silicide l6 Antimony sulphide. 10 Natural occurring glass 10 It is evident that the latter example may be used for centerfire cartridges and shot shells.

It is to be distinctly understood that such a natural occurring glass may be used in varying types of priming mixtures, and that the precise amount of each ingredient may vary, and that the above are merely examples.

By means of the invention herein, applicant has produced a satisfactory priming composition by the use of a comminuted natural occurring glass, and it is to be understood that the torea,27a,sso a going priming mixtures are merely typical thereof and the appended claims are to be broadly construed. v

What is claimed is:

l. A priming mixture including a zoisitic aplite rock.

2. An ammunition priming mixture containing zoisitic aplite rock having substantially the following mineralogical composition:

aplite rock of a chemical composition substantially as follows:

. Per cent Silica 59.5 Ferrix oxide .35 Alumina 25.0 Calcium oxide 6.9 Soda and potash 7.8 WILLI BRU'N.. 

